Luth Haroon / SD_modified

SD card interface

mbed-export/PwmOut.h@0:22612ae617a0, 2012-10-08 (annotated)

Committer:
lharoon
Date:
Mon Oct 08 11:14:07 2012 +0000
Revision:
0:22612ae617a0
1st edition

Who changed what in which revision?

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lharoon 0:22612ae617a0 1 /* mbed Microcontroller Library - PwmOut
lharoon 0:22612ae617a0 2 * Copyright (c) 2007-2011 ARM Limited. All rights reserved.
lharoon 0:22612ae617a0 3 */
lharoon 0:22612ae617a0 4
lharoon 0:22612ae617a0 5 #ifndef MBED_PWMOUT_H
lharoon 0:22612ae617a0 6 #define MBED_PWMOUT_H
lharoon 0:22612ae617a0 7
lharoon 0:22612ae617a0 8 #include "device.h"
lharoon 0:22612ae617a0 9
lharoon 0:22612ae617a0 10 #if DEVICE_PWMOUT
lharoon 0:22612ae617a0 11
lharoon 0:22612ae617a0 12 #include "platform.h"
lharoon 0:22612ae617a0 13 #include "PinNames.h"
lharoon 0:22612ae617a0 14 #include "PeripheralNames.h"
lharoon 0:22612ae617a0 15 #include "Base.h"
lharoon 0:22612ae617a0 16
lharoon 0:22612ae617a0 17 namespace mbed {
lharoon 0:22612ae617a0 18
lharoon 0:22612ae617a0 19 /* Class: PwmOut
lharoon 0:22612ae617a0 20 * A pulse-width modulation digital output
lharoon 0:22612ae617a0 21 *
lharoon 0:22612ae617a0 22 * Example
lharoon 0:22612ae617a0 23 * > // Fade a led on.
lharoon 0:22612ae617a0 24 * > #include "mbed.h"
lharoon 0:22612ae617a0 25 * >
lharoon 0:22612ae617a0 26 * > PwmOut led(LED1);
lharoon 0:22612ae617a0 27 * >
lharoon 0:22612ae617a0 28 * > int main() {
lharoon 0:22612ae617a0 29 * > while(1) {
lharoon 0:22612ae617a0 30 * > led = led + 0.01;
lharoon 0:22612ae617a0 31 * > wait(0.2);
lharoon 0:22612ae617a0 32 * > if(led == 1.0) {
lharoon 0:22612ae617a0 33 * > led = 0;
lharoon 0:22612ae617a0 34 * > }
lharoon 0:22612ae617a0 35 * > }
lharoon 0:22612ae617a0 36 * > }
lharoon 0:22612ae617a0 37 *
lharoon 0:22612ae617a0 38 * Note that on the LPC1768 and LPC2368, the PWMs all share the same
lharoon 0:22612ae617a0 39 * period - if you change the period for one, you change it for all.
lharoon 0:22612ae617a0 40 * Although routines that change the period maintain the duty cycle
lharoon 0:22612ae617a0 41 * for its PWM, all other PWMs will require their duty cycle to be
lharoon 0:22612ae617a0 42 * refreshed.
lharoon 0:22612ae617a0 43 */
lharoon 0:22612ae617a0 44 class PwmOut : public Base {
lharoon 0:22612ae617a0 45
lharoon 0:22612ae617a0 46 public:
lharoon 0:22612ae617a0 47
lharoon 0:22612ae617a0 48 /* Constructor: PwmOut
lharoon 0:22612ae617a0 49 * Create a PwmOut connected to the specified pin
lharoon 0:22612ae617a0 50 *
lharoon 0:22612ae617a0 51 * Variables:
lharoon 0:22612ae617a0 52 * pin - PwmOut pin to connect to
lharoon 0:22612ae617a0 53 */
lharoon 0:22612ae617a0 54 PwmOut(PinName pin, const char *name = NULL);
lharoon 0:22612ae617a0 55
lharoon 0:22612ae617a0 56 /* Function: write
lharoon 0:22612ae617a0 57 * Set the ouput duty-cycle, specified as a percentage (float)
lharoon 0:22612ae617a0 58 *
lharoon 0:22612ae617a0 59 * Variables:
lharoon 0:22612ae617a0 60 * value - A floating-point value representing the output duty-cycle,
lharoon 0:22612ae617a0 61 * specified as a percentage. The value should lie between
lharoon 0:22612ae617a0 62 * 0.0f (representing on 0%) and 1.0f (representing on 100%).
lharoon 0:22612ae617a0 63 * Values outside this range will be saturated to 0.0f or 1.0f.
lharoon 0:22612ae617a0 64 */
lharoon 0:22612ae617a0 65 void write(float value);
lharoon 0:22612ae617a0 66
lharoon 0:22612ae617a0 67 /* Function: read
lharoon 0:22612ae617a0 68 * Return the current output duty-cycle setting, measured as a percentage (float)
lharoon 0:22612ae617a0 69 *
lharoon 0:22612ae617a0 70 * Variables:
lharoon 0:22612ae617a0 71 * returns - A floating-point value representing the current duty-cycle being output on the pin,
lharoon 0:22612ae617a0 72 * measured as a percentage. The returned value will lie between
lharoon 0:22612ae617a0 73 * 0.0f (representing on 0%) and 1.0f (representing on 100%).
lharoon 0:22612ae617a0 74 *
lharoon 0:22612ae617a0 75 * Note:
lharoon 0:22612ae617a0 76 * This value may not match exactly the value set by a previous <write>.
lharoon 0:22612ae617a0 77 */
lharoon 0:22612ae617a0 78 float read();
lharoon 0:22612ae617a0 79
lharoon 0:22612ae617a0 80 /* Function: period
lharoon 0:22612ae617a0 81 * Set the PWM period, specified in seconds (float), keeping the
lharoon 0:22612ae617a0 82 * duty cycle the same.
lharoon 0:22612ae617a0 83 *
lharoon 0:22612ae617a0 84 * Note:
lharoon 0:22612ae617a0 85 * The resolution is currently in microseconds; periods smaller than this
lharoon 0:22612ae617a0 86 * will be set to zero.
lharoon 0:22612ae617a0 87 */
lharoon 0:22612ae617a0 88 void period(float seconds);
lharoon 0:22612ae617a0 89
lharoon 0:22612ae617a0 90 /* Function: period_ms
lharoon 0:22612ae617a0 91 * Set the PWM period, specified in milli-seconds (int), keeping the
lharoon 0:22612ae617a0 92 * duty cycle the same.
lharoon 0:22612ae617a0 93 */
lharoon 0:22612ae617a0 94 void period_ms(int ms);
lharoon 0:22612ae617a0 95
lharoon 0:22612ae617a0 96 /* Function: period_us
lharoon 0:22612ae617a0 97 * Set the PWM period, specified in micro-seconds (int), keeping the
lharoon 0:22612ae617a0 98 * duty cycle the same.
lharoon 0:22612ae617a0 99 */
lharoon 0:22612ae617a0 100 void period_us(int us);
lharoon 0:22612ae617a0 101
lharoon 0:22612ae617a0 102 /* Function: pulsewidth
lharoon 0:22612ae617a0 103 * Set the PWM pulsewidth, specified in seconds (float), keeping the
lharoon 0:22612ae617a0 104 * period the same.
lharoon 0:22612ae617a0 105 */
lharoon 0:22612ae617a0 106 void pulsewidth(float seconds);
lharoon 0:22612ae617a0 107
lharoon 0:22612ae617a0 108 /* Function: pulsewidth_ms
lharoon 0:22612ae617a0 109 * Set the PWM pulsewidth, specified in milli-seconds (int), keeping
lharoon 0:22612ae617a0 110 * the period the same.
lharoon 0:22612ae617a0 111 */
lharoon 0:22612ae617a0 112 void pulsewidth_ms(int ms);
lharoon 0:22612ae617a0 113
lharoon 0:22612ae617a0 114 /* Function: pulsewidth_us
lharoon 0:22612ae617a0 115 * Set the PWM pulsewidth, specified in micro-seconds (int), keeping
lharoon 0:22612ae617a0 116 * the period the same.
lharoon 0:22612ae617a0 117 */
lharoon 0:22612ae617a0 118 void pulsewidth_us(int us);
lharoon 0:22612ae617a0 119
lharoon 0:22612ae617a0 120 #ifdef MBED_OPERATORS
lharoon 0:22612ae617a0 121 /* Function: operator=
lharoon 0:22612ae617a0 122 * A operator shorthand for <write()>
lharoon 0:22612ae617a0 123 */
lharoon 0:22612ae617a0 124 PwmOut& operator= (float value);
lharoon 0:22612ae617a0 125 PwmOut& operator= (PwmOut& rhs);
lharoon 0:22612ae617a0 126
lharoon 0:22612ae617a0 127 /* Function: operator float()
lharoon 0:22612ae617a0 128 * An operator shorthand for <read()>
lharoon 0:22612ae617a0 129 */
lharoon 0:22612ae617a0 130 operator float();
lharoon 0:22612ae617a0 131 #endif
lharoon 0:22612ae617a0 132
lharoon 0:22612ae617a0 133 #ifdef MBED_RPC
lharoon 0:22612ae617a0 134 virtual const struct rpc_method *get_rpc_methods();
lharoon 0:22612ae617a0 135 static struct rpc_class *get_rpc_class();
lharoon 0:22612ae617a0 136 #endif
lharoon 0:22612ae617a0 137
lharoon 0:22612ae617a0 138 protected:
lharoon 0:22612ae617a0 139
lharoon 0:22612ae617a0 140 PWMName _pwm;
lharoon 0:22612ae617a0 141
lharoon 0:22612ae617a0 142 };
lharoon 0:22612ae617a0 143
lharoon 0:22612ae617a0 144 } // namespace mbed
lharoon 0:22612ae617a0 145
lharoon 0:22612ae617a0 146 #endif
lharoon 0:22612ae617a0 147
lharoon 0:22612ae617a0 148 #endif